Epileptic surgery is a treatment option for patients with epilepsy who do not respond to multiple antiepileptic drugs. After detailed investigations to determine the epileptic focus and assess the surrounding functional brain regions, a tailored resection of the epileptic focus is performed to facilitate the cessation of seizures. We have combined the state-of-the-art neurophysiological methods for exploring and preserving functional brain networks, including wide-band electrocorticogram (ECoG) analysis, to investigate neural activities during tasks, the high-frequency electrical cortical stimulation essential for performing tasks, and the low-frequency or single-pulse electrical stimulation for effective connectivity determined by recording cortico-cortical evoked potentials (CCEPs). In this review, we introduce our recent attempts at elucidating the higher-order motor function and dual-language pathway. Regarding higher-order motor control, we report the findings of our recent studies on the brain areas responsible for reaching the parieto-frontal network for various complex behaviors and the multi-spectrum algorithm for motor mapping. Regarding language function, we review the contemporary concepts of the dual-language pathway and introduce our recent CCEP study that explored the dual-language streams. This study showed that each subdivision of the inferior frontal gyrus has different connectivity to the temporal lobe with an anteroposterior gradient and supports the classical connectivity concept of Dejerine ; the frontal lobe is connected to the temporal lobe through the arcuate fasciculus and a double fan-shaped structure anchored at the limen insulae.

  Connectome analysis has advanced the understanding of the function of macro-level circuits between brain areas. It is important to understand not only the anatomical connections but also the functional roles of these connections. In this article, we introduce connectivity analysis between brain regions by using multimodal magnetic resonance imaging.

  In this paper, we propose a brain decoding method for the generation of natural language descriptions based on human brain activity by a deep learning model.

  In addition, to elucidate brain functions, we focused on predictive coding, which is hypothesized to be one of the functions of the cerebral cortex. We investigated the agreement between the predictions of deep learning model and the actual brain activity data to test the predictive coding hypothesis. Furthermore, we propose a method for generating images from human brain activity data by using the same validation model.

  Regenerative medicine studies using mesenchymal stem cells, which are somatic stem cells, have already been conducted as clinical studies and clinical trials in Japan and overseas, mainly for cerebral infarction and spinal cord injury. Our work has focused on neural crest-derived mesenchymal stem cells that have the same origin as the nervous system, and recently established mesenchymal stem cells from the skull. Skull-derived mesenchymal stem cells have superior properties in neuroregeneration therapy and in terms of safety and efficacy for cell therapy compared with commonly used mesenchymal stem cells derived from the mesoderm, such as the bone marrow. We are currently conducting clinical research to confirm these results.

  On the other hand, regenerative medicine is considered to be a new treatment modality as a radical treatment procedure or strategy that does not leave sequelae or disorders . However, as clinical trials progress, the importance of rehabilitation after stem cell transplantation is being understood. We are also studying and developing walking support robots for regenerative medicine, and are proceeding with the integration of cell therapy and robot rehabilitation using in-house data.

  Takayasu's arteritis is a rare and idiopathic systematic inflammatory disease that affects the aorta and its major branches, potentially causing cerebrovascular complications. Treatment of Takayasu's arteritis has focused on controlling inflammation with medications such as immunosuppressants and steroids. Surgical intervention is indicated only for limited cases.

  We report the case of a 30-year-old woman with Takayasu's arteritis presenting with left hemiparesis. Magnetic resonance imaging revealed acute ischemic stroke of the right caudate head and right middle cerebral artery territory. Computed tomography angiography revealed acute tandem lesions, including occlusion of the right common carotid artery at the origin and embolic occlusion of the right internal carotid artery at the intracranial portion. The patient had been diagnosed with Takayasu's arteritis and was prescribed glucocorticoid therapy. As the symptoms progressed rapidly, percutaneous transluminal angioplasty was performed for the right common carotid artery and mechanical thrombectomy for the right internal carotid artery. In parallel, high-dose steroids and immunosuppressants were administered. Postoperatively, she recovered well from her hemiparesis to modified Rankin Scale 1 at discharge.

  Combined medical and endovascular treatment is indicated in particularly severe cases of acute stroke associated with Takayasu's arteritis.

  The frequency of concomitant pituitary tumors during pregnancy is rare. We report the case of patient with prolactin-producing pituitary adenoma with pituitary apoplexy during third trimester pregnancy who underwent an emergency surgery. A 21-year-old woman was diagnosed with prolactin-producing pituitary adenoma 3 years ago. After cabergoline (CAB) treatment was started, she became pregnant 2 years later and discontinued the CAB. Afterward, she developed bitemporal hemianopsia. Her serum PRL level was 647.0ng/ml. Her MRI revealed a sellar/presellar tumor that showed fluid-fluid level, and the optic chiasma was compressed upward. She underwent transsphenoidal surgery after cesarean section. Histopathological examination of the tumor revealed a sparsely granulated lactotroph adenoma (SGLA) with aggressive findings. Her visual field defect was alleviated after surgery. SGLA accounts for the majority of prolactin-producing pituitary adenomas. Patients with SGLA usually follow a benign course. Physiological changes due to pregnancy and discontinuation of CAB can affect the development of pituitary apoplexy and aggressive findings. In such cases, integrative treatment involving the cooperation between clinical departments is necessary.